The U.S. Securities and Exchange Commission (SEC) is warning investors about fraudsters that are impersonating SEC employees in a bid to trick investors into revealing personal information.

In the investor alert issued Wednesday, the SEC stresses that it doesn’t contact investors to confirm trades, set up trading accounts, or record the details of trades.

The regulator also released an audio recording of one of these calls, which was made by a quick-thinking investor, who suspected fraud.

“The audio recording is what fraud sounds like,” says Lori Schock, director of the SEC’s Office of Investor Education and Advocacy, in a statement.

“We included the recording in our investor alert so investors can hear the lies and high pressure tactics imposters use to cheat potential victims out of their money.”